Apparatus for feeding powdered fuel



Sept. 25, 1928.

1,685,331 w. L. M LAUGHLIN ET AL APPARATUS FOR FEEDING POWDERED FUEL Filed July 16, 1927 2 Sheets-Sheet 1 Sept. 25, 1928.

1,685,331 w. L. MOLAUGHLIN ET AL APPARATUS FOR FEEDING POWDERED FUEL Filed July 16, 1927 2 Sheets-Sheet 2 Patented Sept. 25, 1928 UNITED STATES PATENT OFFICE.

WILSON L. MOLAUGHLIN AND HERROLD L. MeIiAUGHIIIN, OF DES MOINES, IOWA.

APPARATUS FOR FEEDING POWDERED FUEL.

Application filed July 16,

This invention relates to an apparatus for feeding powdered fuel such as comminuted coal and mixing this fuel with air so as to secure the perfect combustion of the same 6 ghen it is projected into a combustion cham- The principal object, therefore, of our invention is to provide a device for successfully feeding pulverized fuel such as powdered coal into a furnace or the like.

A further object is to provide a powdered fuel feeding device that is under the control of the operator at all times.

A still further object is to provide a de 16 vice of this character in which the feeding of fuel will be regular and uniform and in which arching and flooding of the fuel will be eliminated.

A still further object of this invention is to 80 provide a powdered fuel feeding device that may readily be adjusted for feeding any desired amount of pulverized fuel relative to the amount of air used.

A still further object is to provide a pow- 88 dered fuel feeding apparatus having a rotatably mounted feeding cylinder, in the periphery of which are receiving scoops adjustable relative to their depth.

A further object is to provide a feeder for powdered fuel that is economical in manu facture and durable in use.

These and other objects will be apparent to those skilled in the art.

Our invention consists in the construction,

to arrangement and combination of the various parts of the device, whereby the objects contemplated are attained as hereinafter more fully set forth, pointed out in our claims and illustrated in the accompanying drawings, in

which:

Fig. 1 is a top plan view of our fuel feeder ready for use.

Fig. 2 is a side view of our invention with a section cut away to illustrate the rotatably mounted feeding cylinder.

F ig.'3 is an end View of the powdered fuel feeder ready for use.

Fig. 4 is a cross sectional view of our apparatus taken on line 4 4 of Fig. 2 and more fully illustrates its construction.

Fig. 5 is a side sectional view of our machine taken on line 5-5 of Fig. 3 and more fully illustrates its interior construction.

:Fig. 6 is a cross sectional view of a portion of the feeding cylinder of the device and. is

taken on line of Fig. 5.

powdered cipal difficulties in the use of finely powdered,

coal or like material as a fuel for commercial purposes, is the difficulty of obtaining the correct mixture of fuel withythe proper amount of air so as to provide for the proper carburation of the-coal. Another difficulty arises in feeding pulverized fuel to fuel burners with the present types of powdered fuel feeders, because of the tendency of the fuel even when dry, to pack in the storage tank, and bcause of its tendency to arch. This interferes with the even feed of the fuel and causes either a diminution in the rate of feed or what is known as flooding whenever an arch in the material breaks. We have overcome all of these difiiculties with our device as will be appreciated by those skilled in the art.

We have used the numeral 10 to designate the stand portion of our device; Mounted upon and near the center of this stand is the hopper 11, designed to hold a supply of powdered fuel. Rotatably mounted in the bearing members 12 and 13 secured to the lower end of this hopper is the shaft 14-. Secured on this shaft and in the lower portion of the hopper 11, is our feeding cylinder comprising a pluralityof solid wheels 15, each having notches in their periphery, as shown in Fig. 6. In between each of these wheels 15 is a disk 17 which, with the notches 16, form scoops for obtaining powdered fuel from the ho per 11 and delivering it to the receiving clamber communicating with the lower side of the cylinder and secured to the stand 10 by suitable means, as shown in the drawings. The numerals 19 and 20 designate guard plates of cylindrical form embracing each side of the feeding cylinder, as shown in Fig. 4. By this construction, above described, if the shaft 14 is rotated, the feeding cylinder will obtain the powdered fuel from the hopper 11 and deposit it in the receiving chamber 18. To regulate the amount of fuel obtained by each scoop as it passes through the powdered fuel in the hopper 1.1, we have provided an adjustable auxiliary scoop bottom late 21 in each notch 16. Each of these ad ustable bottom plates may be placed in any desired position by the set screw 22 threaded through the'back end portion of that plate and having its end engaging the bottom of the notch, as shown in Fig, 6. The plate itself is held in its respective notch by a small cap screw 23 passing through the same at av point near its forward end and threaded into the Wheel 15. To adjust these plates, the cap screw 23 should first be loosened and the set screw 22 rotated until the desired adjustment of the plate is obtained, then the cap screw 23 should'be tightened, in order to securely hold the plate permanently in that desired position. The numeral 24 designates a centrifugal fan for drawing air through the receiving chamber 18, which communicates at its opposite end with the outside atmosphere through the pipe 25, thereby drawing all powdered fuel deposited in the chamber by the feeding cylinder and forcing it and the air through the pipe 26 to a powdered fuel burner, not shown. This een trifugal fan is actuated by the electric motor 27 and thoroughly mixes the powdered fuel and air before the same passes from the pipes 26. The numeral 28 designates a;plurality of spreader plates inthe receiving chamber 18, extending downwardly and slightly toward the fan 24. These spreader plates receive the powdered fuel from the feeding cylinder and spread the same evenly in the chamberbeforethe same reachesthe centrifugal fan 24. The amount of air entering the fan through the receiving chamber 18 is regulated by the gate valve 29 slidably mounted in the air inlet pipe 25. lhe 1 111- meral 30 designates a pinion permanently secured to the armature shaft 31 of the motor 27. Rotatably mounted in the bearing members 32' secured on the stand 10 is the shaft 33.

.Permanently secured to this shaft 33 is a sprocket wheel 34 in operative engagement with the pinion 30. Permanently secured to this shaft 33 is the pinion 35 in operative engagement with a large sprocket wheel 36 permanently secured to the shaft 14, as shown in Figs. 2, 3, and 5. 'By this arrangement, when the electric motor is rotating, the centrifugal fan 24.- and the feeding cylinder will be actuated, but the speed of-rotation of the feeding cylinder is considerably less than the fan 24, due to the chain of gears herebcfore described. To limit the amount of powdered fuel coming in contact with the feeding cylnder, we have .posite from each other.

11. Permanently secured to this shaft are the two disk plates 39, spaced apart, as shown in Figs-1 and 5. The numeral 40 designates a plurality of rods extending between these two plates and secured thereto by suitable means. It should be noted that these rods are secured to these plates at points not-diametrically opangle as shown in the drawings, these rods, when the shaft 38 is rota-ted,will pass through the powdered fuel in the hopper 11, thereby preventing the arching of the same and working this fuel. toward the forward end of the hopper. Permanently secured to the shaft 38 and on the outside of the hopper 11 is the disk 41 having the pins 42 spaced apart and laterally extending from points near its peripheral edge, as shown in Fig. 3. The numeral 43 designates an arm having one end permanently secured to the shaft 14 and its other end capable of engaging one ofthe pins 42 each time the shaft makes one revolution, thereby slowly rotating the shaft 38.

It, will readily be seen that we have provided a feeder for powdered fuel that is simple in construction and under the control of the operator at all times.

Some changes may be made in the construction and arrangement of our improved appara'tus for feeding powdered fuel without departing from the real spirit and purpose of our invention and it is our intention to cover by our claims, any modified forms of structure or use of mechanical equivalents which may be reasonably included within their scope. M

We claimi 1. In a device of the class described, a hopper, a cylinder rotatably mounted in the bottom of said hopper, a means forrotating said cylinder, scoops formed in the periphery of said cylinder, a means for adjusting the depth of each of said scoops, and an air induction fan for receiving and transferring the fuel fed by the said scoops and air to a burner, for the purposes stated.

2. In a device'of the class described, a hopper,-a feedin cylinder rotatably mounted in the bottom 0' said hopper, a receiving chamber-below said cylinder, an air inlet pipe at one end of said receiving chamber, an induction fan communicating with the other end of said receivin chamber, a plurality of spreader plates in said chamber extending downwardly and forwardly, and a means for rotating said cylinder and said fan.

3. In a device of the class described, a hopper, a feeding cylinder rotatably mounted in the'bottom of said hopper, a sleeve slidably mounted in said hopper and capable of inclosing all or any part of said cylinder from material placed in said hopper, a receiving chamber below said cylinder, an air inlet pipe at one end of said receiving chamber, an air induction fan communicating with the other By extending in the.

end of said receiving chamber for transferring the fuel fed by said cylinder and air from said inlet pipe to a burner, a plurality of spreader ates in said chamber extending downw'ar ly and at an angle towards said fan, and a means for rotating said cylinder and said fan.

4. In a device of the class described, a hopper, a shaft rotatably mounted in the bottom of said hopper, a plurality of wheels permanently secured on said shaft, a plurality of transverse notches formed in the periphery of each of said wheels, a plate adjustably secured in each of said notches, a disk between each of said wheels and on said shaft for inforrotating said shaft.

5. In a device of the class described, a. hopper, a shaft rotatably mounted in the bottom of said hopper, a plurality of wheels permanently secured on said shaft, a plurality of notches formed in the periphery of each of said wheels, a plate in each of said notches, a cap screw passing through the end of each plate and threaded into the respective wheel, a second cap screw threaded into the other end portion of each plate having its forward end capable of engaging the bottom of the respective notch in which said plate is placed, a disk between each of said wheels, and a means for rotating said shaft.

WILSON L. MoLAUGHLIN. HERROLD L. MCLAUGHLIN. 

